Magnetic Resonance Imaging/Transrectal Ultrasound Fusion-Guided Biopsy of the Prostate to Detect High-Grade Cancer

Introduction: Multiparametric magnetic resonance imaging (MRI) has been shown to be a valuable adjunct to identifying suspicious lesions for prostate cancer diagnosis.1 MRI/transrectal ultrasound (MRI/TRUS) fusion platforms allow for the detail and information provided by MRI to be combined with the real-time capabilities of ultrasound in an office-based setting. Additionally, MRI/TRUS fusion platforms have demonstrated improved detection of clinically significant prostate cancer compared to standard of care systematic 12-core transrectal ultrasound biopsies.2 Materials and Methods: This video demonstrates the MRI/TRUS fusion biopsy procedure of a 62-year-old male with a history of elevated serum prostate specific antigen (PSA) in the setting of multiple negative TRUS biopsies. The patient was initially biopsied under the standard of care 12-core TRUS with no evidence of prostate cancer with subsequent TRUS biopsies also demonstrating no evidence of cancer. The patient then elected to undergo MRI/TRUS fusion biopsy. A diagnostic, prebiopsy multiparametric MRI with surface and endorectal coils (ERC) was taken, and identified one lesion that was highly suspicious for prostate cancer based on NIH scoring criteria. To help minimize the MRI/TRUS coregistration error, the TRUS probe can mimic ERC deformation during the US sweep and can be further corrected by the image coregistration software of the platform. The entire fusion biopsy procedure using the UroNav platform is depicted and includes patient preparation, TRUS sweep, MRI/TRUS image coregistration, and targeted and standard biopsy. Screenshots of the UroNav platform during biopsy target acquisition and sampling are shown followed by the 12-core TRUS biopsy.3 Results: Four targeted biopsy cores were taken from the midline anterior apical central gland (two in the axial direction, two in the sagittal direction) with all cores detecting prostate adenocarcinoma. Three of the four targeted cores demonstrated Gleason 4+4=8 disease involving between 30% and 90% of the needle core. All 12 systematic cores failed to demonstrate evidence of prostate adenocarcinoma. Targeted biopsy lengthened the total biopsy procedure time by a few minutes with no additional postoperative complications. System accuracy for tracking prostate motion in phantom studies was shown to be 2.4±1.2 mm.4 Conclusion: The UroNav MRI/TRUS fusion platform enables urologists to quickly and efficiently identify and biopsy MR suspicious lesions in an office-based setting. Acknowledgments: This research was supported by the Intramural Research Program of the NIH, National Cancer Institute, Center for Cancer Research and the Center for Interventional Oncology. The NIH and Philips Healthcare have a cooperative research and development agreement. The NIH and Philips share intellectual property in the field. This research was also made possible through the NIH Medical Research Scholars Program, a public–private partnership supported jointly by the NIH and generous contributions to the Foundation for the NIH from Pfizer, Inc. The Leona M. and Harry B. Helmsley Charitable Trust and the Howard Hughes Medical Institute, as well as other private donors. For a complete list, please visit the Foundation website at www.fnih.org/work/programs-development/medical-research-scholars-program. Additionally, the authors would like to thank the patient, OR, and nursing staff for their help in the filming of this procedure. All authors have no competing financial interests. Runtime of video: 7 mins 21 secs